Murat KAŞIKCI, Ozgur EROGUL, Leyla ERYİGİT EROGUL

KERATOKONUSLU HASTALARDA ÖN SEGMENT PARAMETRELERİNİN PENTACAM CİHAZI İLE DEĞERLENDİRİLMESİ

AMAÇ: Keratokonus hastalarında hastalığın şiddetine göre ön segment parametrelerinde gözlenen değişikliklerin Pentacam cihazı kullanılarak değerlendirilmesi ve elde edilen ölçümlerin sağlıklı bireylerden elde edilen ölçümler ile karşılaştırılması amaçlanmıştır.GEREÇ VE YÖNTEM: Elli iki keratokonus hastasının 104 gözü ile 60 sağlıklı bireyin 120 gözüne ait Pentacam cihazı verileri retrospektif olarak değerlendirildi. Hastaların demografik özellikleri, korneal ön yüzey ve arka yüzeye ait kurvatür, asferite ve elevasyon değerleri (K1, K2, korneal astigmatizma ve ortalama asferite) ile en ince korneal kalınlık (TCT), apeks korneal kalınlık (ACT), korneal volüm (CV), ön kamara derinliği (ACD), ön kamara açısı (ACA) ve ön kamara volümü (ACV)değerleri kaydedildi.BULGULAR: Keratokonus grubunda (22 Kız, 30 Erkek) ortalama yaş 30.8±11.6 yıl, kontrol grubunda (26 Kız, 34 Erkek) 32.4±12.4 yıl idi. Gruplar yaş ve cinsiyet açısından uyumlu idi (sırasıyla p=0.32, p=0.89). Keratometri değerlerine göre yapılan sınıflamaya göre keratokonus seviyesi 63 göz hafif, 26 göz orta ve 15 gözde ağır keratokonus olarak gruplandı. Keratokonus hastalarında gruplar arasında korneal ön yüzey ve arka yüzeye ait kurvatür, asferite ve elevasyon değerlerinde anlamlı fark bulundu (p<0.001). TCT hafif grupta en yüksek, ağır grupta en düşük saptandı ve gruplar arasındaki fark anlamlı idi (p<0.05). ACD hafif grupta 3.21±0.34, orta grupta 3.27±0.26 ve ağır grupta ise 3.79±0.53 idi ve aradaki fark anlamlı bulundu (p<0.05).SONUÇ: Keratokonus progresyonu ile korneal ön yüzey ve arka yüzeye ait kurvatür, asferite ve elevasyon değerleri ile kornea ön segment parametrelerinde anlamlı değişiklikler gözlenmektedir.

Anahtar Kelimeler:

Anterior segment parameters, asphericity, corneal topography, irregular astigmatism, keratoconus.

EVALUATION OF ANTERIOR SEGMENT PARAMETERS IN PATIENTS WITH KERATOCONUS WITH PENTACAM DEVICE

OBJECTIVE: It was aimed to evaluate the changes observed in the anterior segment parameters in patients with keratoconus using Pentacam device according to the severity of the disease and to compare the determined results with those obtained from the healthy individuals.MATERIAL AND METHODS: The data obtained by the Pentacam device for 104 eyes of 52 keratoconus patients and 120 eyes of 60 healthy individuals were retrospectively evaluated. Demographic features of the patients, the corneal curvature of the anterior and posterior surface, the asphericity and the elevation values (K1, K2, corneal astigmatism, and average asphericity), thinnest corneal thickness (TCT), apex corneal thickness (ACT), corneal volume (CV), anterior chamber depth (ACD), anterior chamber angle (ACA), and anterior chamber volume (ACV) outcomes were recorded.RESULTS: The average age was 30.8±11.6 years in the Keratoconus group (22 Female, 30 Male) and 32.4±12.4 years in the control group (26 Female, 34 Male). The groups were compatible with each other in terms of age and gender (p=0.32, p=0.89, respectively). In the classification based on keratometry readings, keratoconus level was grouped as mild in 63 eyes, medium in 26 eyes, and severe in 15 eyes. In keratoconus patients, there was a significant difference in curvature, asphericity, and elevation values of the corneal anterior and posterior surfaces between the groups (p<0.001). TCT was the highest in the mild group and lowest in the severe group, and the difference between the groups was significant (p<0.05). ACD was 3.21±0.34 in the mild group, 3.27±0.26 in the medium group, and 3.79±0.53 in the severe group, and the difference was also significant (p<0.05).CONCLUSIONS: Significant changes in the values of curvature, asphericity, and elevation of both corneal anterior and posterior surfaces and the parameters of the anterior segment of the cornea are observed with the progression of keratoconus.

Keywords:

Anterior segment parameters, Asphericity, Corneal topography, Irregular astigmatism, Keratoconus,

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